This invention relates generally to improved drills. More particularly, but not by way of limitation, it relates to an improved, self-colleting drill that includes means for easily varying the spacing between the drill bits.
U.S. Pat. No. 2,909,949 issued Oct. 27, 1959 to J. C. Winslow, illustrates a self-colleting power drill that has parallel output shafts for driving two drill bits simultaneously at a particular spacing between the bits. The drill disclosed therein also includes a self-colleting apparatus to securely retain a work piece against the nose member of the drill during the drilling operation. The drill of this invention and the drill illustrated in the Winslow patent are very similar and provide the same function. However, it is not possible in the drill illustrated in the Winslow patent to vary the spacing between the drill bits.
The object of this invention is to provide an improved self-colleting drill having generally parallelly disposed output shafts for driving a pair of spaced drill bits wherein the drill bit spacing can be easily and quickly changed.